Replication Guides: Instrumenting Your Own Project MOC

Replication Guides: Instrumenting Your Own Project

These four guides are a hand-off package: they let another team stand up the same OpenTelemetry instrumentation pattern used in SignalForge, in their own repository, without first learning this lab’s full architecture.

They differ from the rest of this site’s documentation on purpose. Pages like otel-patterns.md and observability/otel-contracts.md explain what SignalForge does and why, for people already working in this codebase. These guides are ordered, numbered, copy-paste instructions for doing the same thing in a different repository — install this, write this, set this env var, verify this. Where a step needs the “why,” it links out to the reference docs rather than re-explaining it.

The one assumption that makes this concrete instead of generic

Same stack. .NET 8 (ASP.NET Core minimal APIs + gRPC), Python 3.12 (FastAPI), Angular, RabbitMQ, Grafana Cloud (or a self-hosted Tempo/Mimir/Loki/Jaeger/Prometheus stack), Kubernetes + Helm. Every package version, environment variable, and code snippet below is exactly what this project runs today — verified against live source, not against older documentation, which in a few places had drifted from the actual code (noted inline where it matters). If your target stack differs, use these as a concrete worked example rather than a literal transcript.

Guides

Guide	Covers
Guide: Collector & Pipeline Setup	Stand up the Grafana Alloy + grafana/k8s-monitoring Helm chart pipeline every app below sends signals to — do this first
Guide: .NET Instrumentation	ASP.NET Core / gRPC services: SDK wiring, custom spans/metrics, RabbitMQ producer-side async propagation (outbox pattern)
Guide: Python Instrumentation	FastAPI service: SDK wiring, RabbitMQ consumer-side async propagation (SpanLink), log correlation
Guide: Frontend RUM Instrumentation	Angular + Grafana Faro: browser telemetry, runtime config injection, browser-to-backend trace linkage

Recommended order

1. Collector & Pipeline Setup first. The app-side guides all assume there’s a live OTLP endpoint to send signals to and a Grafana instance to see them in. Standing this up first means every later step has something to verify against immediately.
2. The three app-side guides, in any order (or in parallel across teams) — .NET, Python, Frontend RUM don’t depend on each other’s completion, only on step 1.
3. End-to-end verification — each guide ends with its own verify step; once all four are done, confirm a single request’s trace spans all the way from browser → backend → async consumer, per the Cross-Service Trace Topology pattern this project validates with a real integration test.

For the “why” behind any step

• OTel Signal Contracts — exact span/metric/log names this project emits, per service
• OTel Patterns Reference — architecture, propagation, sampling, exemplars
• Observability Pipeline — the Alloy collector’s local vs. cloud mode pipelines, stage by stage
• Grafana Cloud Deployment — credential model, endpoint format requirements
• ADR-002: SpanLink for async RabbitMQ — why the async hop uses a link, not a parent-child span
• ADR-001: Log tailing, not OTLP export — why logs go via stdout + node-level tailing instead of an OTLP log exporter

See the documentation hub for the complete site map.